This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. To determine the development of titers in each CD4+ cell count stratum of antibodies to HPV 6, 11, 16, and 18 above a level of type-specific seropositivity after the quadrivalent HPV recombinant vaccine series